You've likely noticed those calorie counts on so many american men use. Tonight, a revealing study. People consuming more than before? Aditi roy with the story. Reporter: Those calorie labels we see are supposed to help us make healthful food choices. In a new study by carnegie mellon university, 1900 customers were surveyed at a restaurant in new york city. Some were given numbers on the extra calories in a meal. With those numbers in mind, they ate on average 60 more calories than the people who had the basic calorie information listed on the menu. A third of those customers ordered meals with at least 1,000 calories. What did you have? Double cheeseburger. Reporter: Do you know how many calories are in there? Nope. I'm just hungry. Reporter: We were curious to know how many people read those calorie labels. A mocha frappe and a snack wrap. Reporter: Do you know how many calories are in there? Honestly, no. Reporter: Of the ten people we talked to, most people saw the numbers but it didn't change their orders. This researcher believes in order to change eating habits, people need more information on how the food they eat affects their bodies. People who are interested in reducing their calories will be benefited by the calorie labeling. People who do not care, who only want to have their burgers and fries will not do so. Reporter: The authors of the study think people ate more because of a false sense of security. A big mac is 550 calories. When you add in fries and a drink, it puts you over 1,000. So he thinks they were

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